JP2008051650A - In-vessel work system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To ensure the integrity and reliability of an in-vessel work unit. <P>SOLUTION: An in-vessel work system for the work that uses the in-vessel work unit 15 in a reactor pressure vessel 11, in-vessel work is carried out for a region subject to work by the in-vessel work unit 15, by conducting at least one of the control operation of a reactor cooling system 12 for supplying cooling water into the reactor pressure vessel 11, installs an inlet structure for introducing the cooling water from the reactor cooling system 12 to an annulus section 14 and the installation of an isolation wall which isolates an area above the annulus section 14; and guides the in-vessel work unit 15 to the isolated area and also leads the cooling water from the reactor cooling system 12 to the annulus section 14 in response to the temperature and fluid state of reactor water in the annulus section 14 including the region subject to the work. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an in-core work system that performs inspection, preventive maintenance, repair, and the like in a reactor pressure vessel by using an in-core work device at the time of periodic inspection.

  Various proposals have been made in an in-reactor work system for performing operations such as inspection, preventive maintenance, and repair in a reactor pressure vessel.

  For example, an in-reactor inspection device (Patent Document 1) and a swimming-type underwater visual inspection device (Patent Document 2) move an inspection device (underwater vehicle) capable of swimming in the water to an inspection target part to change the visual inspection site. It is to be inspected.

  In addition, the in-furnace structure inspection device (Patent Document 3) has a pair of wheel-type moving mechanisms mounted on a rail for the refueling machine to travel along the rails, and a wire is provided between these wheel-type moving mechanisms. A hanging movement mechanism is attached to this wire so that it can be moved using the wire as a guide, and an underwater television camera is suspended from this hanging movement mechanism to inspect the appearance of the internal structure of the furnace. To do.

  In addition, the in-reactor work platform (Patent Document 4) moves the platform on which the control cable winding device supporting the in-reactor work mechanism is mounted to the water surface or water in the reactor well and the reactor pressure vessel. It is provided freely so that the work inside the reactor can be carried out easily.

On the other hand, Patent Document 5 discloses a water jet peening apparatus that uses a reactor cooling water recirculation pump or the like to increase the water jet peening effect by cavitation, and makes the temperature inside the reactor uniform or rise by the stirring effect. Are listed.
Japanese Patent Laid-Open No. 7-218681 JP-A-7-69284 JP 2000-346976 A JP-A-9-222492 JP-A-7-328860

  However, the devices described in Patent Documents 1 to 4 are not premised on application in the temperature and flow state of reactor water immediately after the reactor is released, and therefore the soundness, reliability, and durability of the device in this environment. There are no considerations on how to improve. In addition, the environmental conditions of the temperature and flow state of the reactor water in the area where the inspection device exists for a long time is grasped, the environmental conditions are adapted to the inspection device, the failure of the inspection device is reduced, and the reliability is improved. There have been no proposals for efficiently realizing in-furnace work.

  Moreover, in order to obtain the effect of water jet peening to the maximum, the device described in Patent Document 5 controls (mainly increases) the water temperature in the furnace using the heat of a recirculation pump or a throwing heater, It does not cool the in-furnace working device and improve its soundness, reliability, and durability.

  Furthermore, in any of the patent documents, when other work such as fuel replacement is performed in parallel with the in-furnace work such as inspection of the in-furnace structure, the work equipment and the like in these both works interfere with each other. It does not describe means for avoiding the risk of interference.

  An object of the present invention is to provide an in-furnace work system that can ensure the soundness and reliability of the in-furnace work apparatus in consideration of the above-described circumstances.

  Another object of the present invention is to provide an in-furnace work system that can suitably avoid interference between the in-furnace work apparatus and work equipment used for other work.

  The present invention relates to an in-reactor work system for working inside a reactor pressure vessel using an in-reactor working device, in accordance with the temperature and flow state of the reactor water in the region including the work target part. Control of the reactor cooling system for supplying cooling water to the reactor, installation of an introduction structure for introducing the cooling water from the reactor cooling system into the region including the work target site, and the region including the work target site. The upper region is isolated, and at least one of guiding the in-reactor working device into the isolated region and installing an isolation wall for guiding the cooling water from the reactor cooling system to the region including the work site is performed. Then, the work target part is worked by the above-mentioned furnace working device.

  According to the present invention, the operation control of the reactor cooling system for supplying cooling water into the reactor pressure vessel according to the temperature and flow state of the reactor water in the region including the work target site, and the reactor cooling system Of the introduction structure for introducing the cooling water into the area including the work target part, isolating the upper area of the area including the work target part, guiding the in-reactor work device into the isolated area, and the reactor cooling system At least one of the installation of the isolation wall which guides the cooling water from the work area to the region including the work target part is performed, and the work target part is worked by the in-furnace work device. From this, since the region including the work target part can be adjusted to a temperature suitable for the in-furnace work apparatus, it is possible to prevent a failure due to the heat of the in-furnace work apparatus, and to improve the soundness and reliability of the in-furnace work apparatus. It can be secured.

  When installing an isolation wall that isolates the upper area of the area including the work target part and guiding the in-furnace work device into this isolated area, interference between the in-furnace work device and work equipment used for other work is avoided. The above-described isolation wall can be preferably avoided.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  The in-reactor work system according to the present embodiment performs in-reactor work such as inspection, preventive maintenance, and repair in the reactor pressure vessel using the in-reactor work device. This is a system that is released, for example, during regular inspections. This in-reactor work system includes the temperature and flow state of the reactor water (particularly in this embodiment, an annulus portion defined by the reactor pressure vessel and the core shroud) including the region to be worked by the in-core work device. The operation control of the reactor cooling system that supplies cooling water into the reactor pressure vessel according to the flow velocity), and the installation of an introduction structure that actively introduces the cooling water from the reactor cooling system into the annulus In addition, the upper region of the annulus part is isolated from the upper region of the core, the in-reactor working device is guided into the isolated region, and the isolation wall is actively guided to the cooling water from the reactor cooling system to the annulus part. To implement at least one of the following. Then, the operation control of these reactor cooling systems, the installation of the introduction structure, and the installation of the isolation wall are performed alone or in combination, so that the in-reactor work is performed on the work target site by the in-reactor work device. Hereinafter, the first to seventh embodiments will be sequentially described.

[A] First embodiment (FIGS. 1 to 3)
FIG. 1 is a system diagram showing a first embodiment of an in-furnace work system according to the present invention. The in-core work system according to the present embodiment involves operation control of a reactor cooling system 12 that supplies cooling water into the reactor pressure vessel 11.

  A core shroud 13 is installed in the reactor pressure vessel 11, and an annulus portion 14 is formed between the reactor pressure vessel 11 and the core shroud 13. A plurality of jet pumps 25 (see FIG. 4) are disposed in the annulus portion 14. During periodic inspections, in-core operations such as inspection, preventive maintenance, and repair of the core shroud 13 and the jet pump 25 are performed using the in-furnace working device 15 in the annulus unit 14. Reference numeral 15A denotes a cable for the in-furnace working device 15.

  In order to cool the inside of the reactor pressure vessel 11 at the time of periodic inspection, the cooled cooling water is supplied from the reactor cooling system 12 in which the system pipe 17 is provided with the cooling pump 18 and the heat exchanger 19. It is supplied into the furnace pressure vessel 11. The reactor cooling system 12 is a reactor recirculation system in which, for example, the cooling pump 18 is a reactor recirculation pump and the heat exchanger 19 is a heat removal system heat exchanger, and a water supply sparger 21 (FIGS. 4, 8, etc.) The cooled cooling water is supplied into the reactor pressure vessel 11 through

  The temperature and flow state (especially the flow velocity) of the reactor water in the reactor pressure vessel 11 including the annulus portion 14 at the time of periodic inspection are the fuel 20 mounted on the core portion 16 inside the core shroud 13 (see FIG. 8) and the shape of the flow path of each part in the reactor pressure vessel 11 and the cooling pump 18 of the reactor cooling system 12. On the other hand, the furnace working device 15 working in the annulus unit 14 is equipped with devices that are easily affected by heat, such as various electronic devices such as sensors and motors. For this reason, an environment suitable for the in-furnace working device 15 is required in the annulus portion 14 where the in-furnace working device 15 works.

  Therefore, in the in-reactor work system of the present embodiment, the operation control of the reactor cooling system 12 is performed by controlling the temperature of the reactor water in the reactor pressure vessel 11, particularly in the annulus portion 14 that is the work area of the in-core work device 15. Control according to the flow state (especially the flow rate).

  That is, the temperature measuring device 22 and the flow velocity measuring device 23 are installed in the annulus portion 14 of the reactor pressure vessel 11. The measured value of the reactor water temperature in the annulus unit 14 measured by the temperature measuring device 22 and the reactor water flow rate in the annulus unit 14 measured by the flow velocity measuring device 23 are transmitted to the reactor water thermal flow state determination device 24. The

The reactor water thermal fluid state determination device 24 determines the thermal fluid state in the annulus unit 14 based on the measured values of the reactor water temperature and the reactor water flow rate in the annulus unit 14, that is, the temperature and flow rate of the reactor water in the annulus unit 14. It is determined whether or not it is suitable for the in-furnace working device 15. Then, when the reactor water thermal fluid state determination device 24 determines that the thermal fluid state of the annulus portion 14 is suitable for the in-reactor work device 15, the operation of the reactor cooling system 12 is stopped and the in-reactor work device is stopped. When the operation mode for starting or continuing the in-reactor operation by 15 is selected and it is determined that the operation is not suitable, the operation of the reactor cooling system 12 is started or continued to stop the in-reactor operation by the in-reactor operation device 15 The cooling operation mode to be selected is selected and executed.

  In the in-furnace heat flow state determination device 24, an upper limit temperature and an upper limit flow velocity for ensuring the soundness of the in-furnace work device 15 are set in order to perform the above-described determination. As shown in FIG. 2, the in-furnace thermal fluid state determination device 24 compares the measured value of the reactor water temperature in the annulus portion 14 with the upper limit temperature (S1), and then determines the reactor water flow velocity in the annulus portion 14. The measured value is compared with the upper limit flow velocity (S2).

Then, the in-furnace thermal fluid state determination device 24 is configured when the measured value of the reactor water temperature in the annulus portion 14 is not more than the upper limit temperature and the measured value of the reactor water flow velocity in the annulus portion 14 is not more than the upper limit flow velocity. Then, it is determined that the heat flow state in the annulus portion 14 is suitable for the in-reactor work device 15, and the cooling pump 18 of the reactor cooling system 12 and the in-reactor work device 15 are made to perform the work mode (S3). When the measured value of the reactor water temperature and the measured value of the reactor water flow velocity are other than those described above, it is determined that the heat flow state of the annulus portion 14 is not suitable for the in-furnace work device 15 and the cooling operation mode is performed (S4). ).

  Thereby, as shown in FIG. 3, the in-furnace working device 15 performs the in-furnace work in the annulus portion 14 only when the reactor water temperature is equal to or lower than the upper limit temperature and the reactor water flow rate is equal to or lower than the upper limit flow rate. It will be. For this reason, in the in-furnace working apparatus 15, the failure resulting from the reactor water temperature and the reactor water flow velocity is reduced.

  In the present embodiment, the reactor water temperature and the reactor water flow velocity in the annulus section 14 are not measured, and the reactor heat flow state determination device 24 analyzes known data relating to the heat flow in the reactor pressure vessel 11. Then, the spatial and temporal fluctuations of the reactor water temperature and the reactor water flow velocity in the annulus section 14 are obtained, and either the operation mode or the cooling operation mode is selected and executed based on the reactor water temperature and the reactor water flow velocity. Also good. In this case, the temperature measuring device 22 and the flow velocity measuring device 23 are not necessary.

  Therefore, according to the said embodiment, there exists the following effect. That is, by controlling the operation of the reactor cooling system 12 for supplying cooling water to the reactor pressure vessel 11 in accordance with the temperature and flow state (particularly the flow rate) of the reactor water in the annulus section 14 in the reactor pressure vessel 11. Then, the in-furnace working device 15 is caused to carry out the in-furnace work in the annulus portion 14. As a result, the in-furnace working device 15 operates within the annulus portion 14 within a range where the reactor water temperature and the reactor water flow rate can be tolerated. Therefore, failures due to these reactor water temperature and reactor water flow velocity are reduced. Soundness and reliability can be ensured.

[B] Second embodiment (FIG. 4)
FIG. 4 is a second embodiment of the in-core work system according to the present invention, in which (A) is a longitudinal sectional view showing one side (half) of the internal structure of the reactor pressure vessel, and (B) is FIG. It is a plane sectional view which meets the IV-IV line of (A). In the second embodiment, the same parts as those in the first embodiment described above are denoted by the same reference numerals, and redundant description is omitted.

  In the in-reactor work system of the present embodiment, an introduction structure that actively introduces cooling water from the reactor cooling system 12 into the annulus portion 14 is installed in the reactor pressure vessel 11 to partially supply the water supply sparger 21. The water supply sparger enclosure plate 30 is surrounded by

  The feed water sparger 21 is located above the core shroud 13 in the reactor pressure vessel 11 at a certain distance from the inner peripheral surface of the reactor pressure vessel 11, and is continuously or discontinuously ring-shaped along the inner peripheral surface. It is formed. Cooling water cooled by the reactor cooling system 12 is supplied into the reactor pressure vessel 11 from the nozzles (not shown) provided at a plurality of locations in the circumferential direction of the feed water sparger 21 at the time of periodic inspection of the reactor.

  The water supply sparger enclosure plate 30 is spaced apart from the core shroud 13 side of the water supply sparger 21 and surrounds the core shroud 13 side of the water supply sparger 21. The water supply sparger enclosure plate 30 has a semicircular cross section, a semi-torus shape, or a cylindrical shape with a part cut away, and is configured in a ring shape continuously or discontinuously along the water supply sparger 21. .

  Therefore, the cooling water from the reactor cooling system 12 injected from the nozzle of the feed water sparger 21 collides with the feed water sparger enclosure plate 30 and flows down and is introduced to the core portion 16 side inside the core shroud 13. More is introduced into the annulus 14 between the shroud 13 and the reactor pressure vessel 11. In this state, the in-furnace working device 15 performs the in-furnace work in the annulus portion 14.

  With the configuration as described above, the present embodiment has the following effects. That is, since the feed water sparger shroud 30 surrounds the core shroud 13 side of the feed water sparger 21, the cooled cooling water from the reactor cooling system 12 is ejected from the feed water sparger 21 and then collides with the feed water sparger shroud 30. Then, the direction is changed to the annulus portion 14 side, the rate of flowing into the core portion 16 is decreased, and the rate of flowing into the annulus portion 14 is increased. As a result, the temperature in the annulus portion 14 is lowered, the failure due to heat of the in-furnace work device 15 working in the annulus portion 14 is reduced, and the soundness and reliability of the in-furnace work device 15 are improved. Can do.

[C] Third embodiment (FIG. 5)
FIG. 5 shows a third embodiment of the in-core work system according to the present invention, in which (A) is a longitudinal sectional view showing one side (half) of the internal structure of the reactor pressure vessel, and (B) is FIG. It is sectional drawing which follows the VV line of (A). In the third embodiment, the same parts as those in the first and second embodiments described above are denoted by the same reference numerals, and redundant description is omitted.

  In the in-reactor work system of the present embodiment, an introduction structure that actively introduces cooling water from the reactor cooling system 12 into the annulus portion 14 is installed in the reactor pressure vessel 11 to partially supply the water supply sparger 21. The water supply sparger enclosure plate 30 and the cooling water transfer pipe 31 extending downward from the water supply sparger enclosure plate 30 are configured.

  The cooling water transfer pipe 31 extends vertically downward from a plurality of locations in the extending direction of the water supply sparger enclosure plate 30 toward the annulus portion 14 and reaches the annulus portion 14. The cooling water transfer pipe 31 is formed in a semi-cylindrical shape, a cylindrical shape, or a rectangular tube shape. Therefore, the cooling water from the reactor cooling system 12 ejected from the nozzle of the feed water sparger 21 collides with the feed water sparger enclosure plate 30 and flows down into the annulus portion 14, and a part of the collision with the feed water sparger enclosure plate 30 is cooled. The water is introduced directly into the annulus 14 along the water transfer pipe 31. In this state, the in-furnace working device 15 performs the in-furnace work in the annulus portion 14.

  With the configuration as described above, the following effects can be obtained according to the present embodiment. That is, the water supply sparger enclosure plate 30 surrounds the core shroud 13 side of the water supply sparger 21, and the cooling water transfer pipe 31 extends from the water supply sparger enclosure plate 30 toward the annulus portion 14. From this, the cooled cooling water from the reactor cooling system 12 is ejected from the feed water sparger 21, then collides with the feed water sparger enclosure plate 30, changes its direction toward the annulus portion 14, and flows down into the annulus portion 14. . As a result, the ratio of flowing into the core portion 14 decreases and the ratio of flowing into the annulus portion 14 increases. Further, a part of the cooling water colliding with the water supply sparger enclosure plate 30 is directly transferred into the annulus part 14 through the cooling water transfer pipe 31, so that the inside of the annulus part 14 can be cooled more suitably. . As a result, the failure due to the heat of the in-furnace working device 15 working in the annulus portion 14 is further reduced, and the soundness and workability of the in-furnace working device 15 can be improved.

[D] Fourth embodiment (FIG. 6)
FIG. 6 is a fourth embodiment of the in-core work system according to the present invention, in which (A) is a longitudinal sectional view showing one side (half) of the internal structure of the reactor pressure vessel, and (B) is FIG. It is sectional drawing which follows the VI-VI line of (A). In the fourth embodiment, the same parts as those in the first and second embodiments described above are denoted by the same reference numerals, and redundant description is omitted.

  In the in-reactor working system of the present embodiment, an introduction structure that actively introduces cooling water from the reactor cooling system 12 into the annulus portion 14 is provided in a position facing the feed water sparger 21 in the reactor pressure vessel 11. And a shroud 32 installed at the upper end of the core shroud 13. The surrounding plate 32 is formed to extend upward from the upper end of the core shroud 13 over substantially the entire circumference of the core shroud 13.

  Accordingly, the cooling water from the reactor cooling system 12 injected from the nozzle of the feed water sparger 21 collides with the enclosure plate 32 and flows down and is introduced into the core portion 16 side inside the core shroud 13 rather than being introduced into the core shroud 13 side. More is introduced into the annulus 14 between the reactor 13 and the reactor pressure vessel 11. In this state, the in-furnace working device 15 performs the in-furnace work in the annulus portion 14.

  With the configuration as described above, the present embodiment has the following effects. That is, since the enclosure plate 32 is installed at the upper end portion of the core shroud 13 so as to face the feed water sparger 21, the cooled cooling water from the reactor cooling system 12 is ejected from the feed water sparger 21 and then the enclosure plate. It collides with 32 and turns to the annulus portion 14 side, the rate of flowing into the core portion 16 decreases, and the rate of flowing into the annulus portion 14 increases. As a result, the temperature in the annulus portion 14 is lowered, the failure due to heat of the in-furnace work device 15 working in the annulus portion 14 is reduced, and the soundness and reliability of the in-furnace work device 15 are improved. Can do.

[E] Fifth embodiment (FIG. 7)
7 is a fifth embodiment of an in-core work system according to the present invention, in which (A) is a longitudinal sectional view showing one side (half) of the internal structure of the reactor pressure vessel, and (B) is FIG. It is a plane sectional view which meets the VII-VII line of (A). In the fifth embodiment, the same parts as those in the first and second embodiments described above are denoted by the same reference numerals, and redundant description is omitted.

  In the in-reactor work system of the present embodiment, the introduction structure that actively introduces cooling water from the reactor cooling system 12 to the annulus portion 14 communicates with the annulus portion 14 of the reactor pressure vessel 11, and This is a cooling water inlet 33 provided on the side of the pressure vessel 11. One or more cooling water inlets 33 are provided on the side of the reactor pressure vessel 11. The cooling water cooled by the reactor cooling system 12 directly flows into the annulus portion 14 of the reactor heat vessel 11 through the cooling water inlet 33.

  In the present embodiment, as shown in FIG. 7, a surrounding plate 32 may be provided at a position facing the water supply sparger 21. FIG. 7 also shows a reactor recirculation pump 34 as a cooling pump 18 (FIG. 1) of the reactor recirculation system 12 (FIG. 1), and the reactor recirculation pump 34. The system piping 17 toward the jet pump 25 is shown. Although not shown, the system pipe 17 is also connected to the water supply sparger 21 and the cooling water inlet 33.

  With the configuration as described above, the present embodiment has the following effects. That is, since the cooled cooling water flows directly from the reactor cooling system 12 through the cooling water inlet 33 into the annulus part 14 of the reactor pressure vessel 11, the temperature in the annulus part 14 decreases, and this Failure due to heat of the in-furnace working device 15 working in the annulus portion 14 is reduced, and the soundness and reliability of the in-furnace working device 15 can be improved.

[F] Sixth embodiment (FIGS. 8 to 10)
FIG. 8 is a longitudinal sectional view showing the internal structure of the reactor pressure vessel in the sixth embodiment of the in-core work system according to the present invention. In the sixth embodiment, the same parts as those in the first and second embodiments described above are denoted by the same reference numerals, and redundant description is omitted.

  In the in-core work system of the present embodiment, the isolation wall 40 that isolates the upper region 41 of the annulus portion 14, which is the work region of the in-core work device 15, from the upper region of the core portion 16 (that is, the upper core region 42). Is installed in the core shroud 13. The in-reactor working device 15 is introduced into an isolation region 43 (in this embodiment, an upper region 41 of the annulus portion 14) that is isolated by the isolation wall 40 and surrounded by the isolation wall 40 and the reactor pressure vessel 11. The cable 15A of the in-furnace working device 15 is always positioned in the isolation region 43. The in-furnace working device 15 reaches the inside of the annulus part 14 through the isolation region 43 and performs the in-furnace work in the annulus part 14.

  The isolation wall 40 is formed in a cylindrical shape (for example, a cylindrical shape) having a height where the upper portion faces the water supply sparger 21 with the lower end portion installed in the core shroud 13. Thereby, the cooling water ejected from the water supply sparger 21 collides with the isolation wall 40 and changes its direction, flows down in the isolation region 43 and is guided into the annulus portion 14, and cools the annulus portion 14.

The fuel 20 is mounted on the core portion 16 adjacent to the annulus portion 14 via the core shroud 13, and the rising flow of the reactor water in the high temperature state is caused by the collapse of the fuel 20 even during the periodic inspection. Occurs. This reactor water is assumed to flow over the upper end portion of the isolation wall 40 and flow into the annulus portion 14. However, the cooling water ejected by the water supply sparger 21 is guided into the annulus part 14 through the isolation wall 40 and cools the inside of the annulus part 14, so that the temperature inside the annulus part 14 is suitable for the in-furnace working device 15. Retained in the environment. In addition, the code | symbol 49 in FIG. 8 shows a core spray piping.

  In addition, when the in-core work device 15 performs the in-core work in the annulus portion 14, for example, during periodic inspection, a fuel exchanger (not shown) is installed above the core portion 16 and the core upper region 42, and this fuel exchanger is used. In some cases, the replacement work of the fuel 20 in the core 16 may be performed. In this case, the main body 15B and the cable 15A of the in-furnace working device 15 may move to an unexpected region due to the flow of the reactor water, and may interfere with the fuel exchanger and the fuel, but the in-furnace working device 15 is isolated. The interference is avoided by introducing the cable 15A into the isolation region 43 by the wall 40 and always positioning the cable 15A in the isolation wall 43.

  As shown in FIG. 9, the separating wall 40 is formed in a cylindrical shape by connecting a plurality of (for example, four) curved plate-shaped constituent elements 44 to each other by a connecting structure 45. The coupling structure 45 is configured to couple adjacent constituent elements 44 using a reinforcing plate 46 and a coupling bolt 47. When the isolation wall 40 is not used, the isolation wall 40 is disassembled into a plurality of component elements 44, whereby the storage space for the isolation wall 40 can be reduced. The isolation wall 40 is disassembled and assembled on the operation floor 48 (see FIG. 11) of the reactor building or in the reactor pressure vessel 11. If the storage space for the isolation wall 40 is secured on the operation floor 48, the isolation wall 40 does not need to be configured to be disassembled and assembled using the coupling structure 45.

  Further, as shown in FIGS. 9 and 10, engagement pieces 50 as engagement portions are installed on the upper and lower portions of the assembled isolation wall 40. The engagement pieces 50 are engaged with the guide rods 51 in the reactor pressure vessel 11, so that the isolation wall 40 is removed when the isolation wall 40 is installed in the reactor pressure vessel 11 or outside the reactor pressure vessel 11. In this case, the isolation wall 40 is guided so that it can move smoothly without interfering with the in-furnace structures such as the feed water sparger 21 and the reactor water spray pipe 49. The guide rod 51 vertically extends into the reactor pressure vessel 11 by a guide rod bracket 52 of the core shroud 13 and a guide rod support 64 (see FIGS. 11 and 15) attached to the inner wall of the reactor pressure vessel 11. It is installed to extend. The guide rod 51 guides the shroud head and the steam separator (both not shown) installed on the upper part of the core shroud 13 during installation and removal.

  Here, when the main steam line plug (not shown) is attached to the steam outlet nozzle of the reactor pressure vessel 11 and the ring garter (not shown) is attached to this plug, In order to avoid interference with the ring gutter, it is not installed on the isolation wall 40. Therefore, the engaging piece 50 is not an essential component for the isolation wall 40 of the present embodiment.

  Further, as shown in FIGS. 8 and 9, a suspension ear 53 as a suspension portion for suspending the isolation wall 40 is installed at the upper end portion of the assembled isolation wall 40. A plurality of (for example, four) suspension ears 53 are installed at symmetrical positions on the upper end of the isolation wall 40, and each has a suspension hole 54. A suspension jig 55 (FIG. 10) coupled to an overhead crane (not shown) of the reactor building is connected to the suspension ear 53, so that the isolation wall 40 is suspended and installed in the reactor pressure vessel 11, It is lifted out of the reactor pressure vessel 11 and removed.

  That is, the lifting jig 55 is configured by intersecting a plurality of beams, for example, two beams, and an overhead crane coupling portion 56 is installed at the intersecting portion, and a hanging cylinder 57 is installed at the tip portion of each beam. An overhead crane hook 58 is attached to the overhead crane coupling portion 56, and by inserting a pin 59 into the overhead crane coupling portion 56, the hook 58 is prevented from coming off from the overhead crane coupling portion 56. Further, the hoisting cylinder 57 is provided with an advancing hose 61 and a retreating hose 62 for moving the rod 60 forward and backward, and both the hoses 61 and 62 are arranged to extend to the operation floor 48. The

  A working medium (air, water, oil, or the like) is suspended and supplied to the cylinder 57 through the advance hose 61, and the working medium is discharged through the retreating hose 62, whereby the rod 60 is advanced. Is inserted into the suspension hole 54 in the suspension ear 53 of the isolation wall 40, and the isolation wall 40 and the suspension jig 55 are connected. In this state, the isolation wall 40 is suspended by the overhead crane via the hanging jig 55. Further, the working medium is supplied to the hoisting cylinder 57 through the retreating hose 62, and the working medium is discharged through the advancing hose 61, whereby the rod 60 is retreated, and the rod 60 is suspended from the isolation wall 40. The separation from the suspension hole 54 in the ear 53 and the connection between the isolation wall 40 and the suspension jig 55 are released.

  Next, the process from the installation of the isolation wall 40 in the reactor pressure vessel 11 to the operation in the reactor by the in-reactor 15 and the subsequent removal of the isolation wall 40 outside the reactor pressure vessel 11 will be described. To do.

  First, the reactor pressure vessel 11 and the reactor well 63 (see FIG. 11) of the reactor building are filled with water. Next, a shroud head (not shown) is removed from the core shroud 13 in the reactor pressure vessel 11. Thereafter, the isolation wall 40 (FIG. 8) is assembled on the operation floor 48, and the assembled isolation wall 40 is temporarily placed on the operation floor 48.

In addition, above the suspension jig 55 (FIG. 10) installed on the operation floor 48, the hook 58 of the overhead crane is coupled to the overhead crane coupling portion 56 using the pin 59, and the suspension jig 55 is It can be lifted or suspended by an overhead crane. In addition, when the hook 58 of the overhead crane and the overhead crane coupling portion 56 of the lifting jig 55 are coupled, a scaffold may be installed on the operation floor 48 and used.

  Next, the suspension crane 55 is lifted by operating the overhead crane, and the suspension cylinder 57 of the suspension jig 55 is inserted into the suspension hole 54 of the suspension ear 53 of the isolation wall 40 temporarily placed on the operation floor 48. The rod 60 is inserted, and the isolation wall 40 and the hanging jig 55 are connected. In this state, the isolation wall 40 is lifted by an overhead crane, and the isolation wall 40 is suspended in the reactor pressure vessel 11.

  At this time, when the engagement piece 50 is installed on the isolation wall 40 at the stage where the isolation wall 40 is suspended in the reactor pressure vessel 11 from the reactor well 63 (see FIG. 11) of the reactor building. Then, the lower engaging piece 50 and the guide bar 51 are engaged. Thereafter, the isolation wall 40 is further suspended, the upper engagement piece 50 is also engaged with the guide rod 51 and suspended, and the isolation wall 40 is seated on the core shroud 13 and installed.

  Thereafter, the rod 60 in the suspension cylinder 57 of the suspension jig 55 is removed from the suspension ear 53 of the isolation wall 40, the connection between the suspension jig 55 and the isolation wall 40 is released and separated, and the suspension jig 55 is taken out from the reactor pressure vessel 11 and temporarily placed on the operation floor 48.

  In this state, the in-core work device 15 is introduced into the isolation region 43 of the isolation wall 40 and lowered to the inside of the annulus portion 14 in the reactor pressure vessel 11. In the annulus portion 14, the in-furnace working device 15 performs the in-furnace work on the core shroud 13, the jet pump 25, and the like.

  At an appropriate timing after the completion of the in-reactor operation, the lifting jig 55 is suspended in the reactor pressure vessel 11 using an overhead crane, seated on the isolation wall 40 in the reactor pressure vessel 11, and suspended. The hanging jig 55 is connected to the isolation wall 40 in the same procedure as the preparation on the previous operation floor 48. Thereafter, the overhead crane is operated to lift the isolation wall 40 via the lifting jig 55, and the isolation wall 40 is seated on the operation floor 48.

  Thereafter, the connection between the lifting jig 55 and the isolation wall 40 is released by the same procedure as when the isolation wall 40 is installed in the core shroud 13 to separate them. Then, the hanging jig 55 is installed on the operation floor 48, and the overhead crane and the hanging jig 55 are separated by removing the pins 59 at the overhead crane connecting portion 56 of the hanging jig 55. To complete.

  Since it is configured as described above, the following effects can be obtained according to the present embodiment.

  That is, the isolation wall 40 installed in the core shroud 13 isolates the upper region 41 of the annulus portion 14 from the core upper region 42, and this isolation wall 40 isolates the cooling water from the water supply sparger 21 from the isolation wall 40. Since the lead is introduced into the annulus portion 14 through the region 43, the inside of the annulus portion 14 can be cooled even when high-temperature reactor water in the core portion 16 flows into the annulus portion 14. As a result, the temperature in the annulus part 14 is adjusted to a temperature suitable for the in-furnace work apparatus 15 that performs the in-furnace work in the annulus part 14. For this reason, the damage by the heat | fever of the working apparatus 15 in a furnace is reduced, the soundness and reliability can be ensured, and durability can be improved. For this reason, the possibility of work interruption due to the failure of the in-furnace work apparatus 15 can be reduced.

  Further, the upper region 41 of the annulus portion 14 and the core upper region 42 are isolated by the isolation wall 40, and work is performed in the annulus portion 14 in the isolation region 43 (that is, the upper region 41) formed by the isolation wall 40. An in-furnace working device 15 is introduced. Therefore, even when the replacement operation of the fuel 20 by the fuel exchanger in the core portion 16 is performed in parallel with the in-furnace operation by the in-furnace operation device 15, the main body 15B of the in-furnace operation device 15 and its cable Since the movement of 15A is regulated by the isolation wall 40, it is possible to prevent the main body 15B and the cable 15A of the in-furnace working apparatus 15 from interfering with the fuel exchanger and the fuel. For this reason, the possibility of interruption of both operations due to the occurrence of interference can be reduced, and the load of monitoring activities for avoiding interference can be reduced.

  Furthermore, by introducing the in-furnace working device 15 into the isolation region 43 of the separating wall 40, the separating wall 40 guides the in-furnace working device 15 when the in-furnace working device 15 is suspended, The work device 15 can be quickly reached the target work position.

[G] Seventh embodiment (FIGS. 11 to 16)
FIG. 11 is a longitudinal sectional view showing the internal structure of the reactor pressure vessel in the seventh embodiment of the in-core work system according to the present invention. FIG. 12 is a perspective view showing the isolation wall constituting member of FIG. FIG. 13 is a perspective view showing the lowermost isolation wall constituting member of FIG. 11. In the seventh embodiment, the same parts as those in the first, second, and sixth embodiments described above are denoted by the same reference numerals, and redundant description is omitted.

  In the in-core work system of the present embodiment, an isolation wall 70 that isolates the upper region 41 of the annulus portion 14 that is the work region of the in-core work device 15 from the core upper region 42 is installed in the core shroud 13. Or it hold | maintains in the state hung up above the core shroud 13, and this isolation wall 70 is comprised by stacking the some isolation wall structural member 71. FIG. Among these isolation wall constituting members 71, the isolation wall constituting member denoted by reference numeral 71A is an isolation wall constituting member located at the lowest level. The isolation region 73 isolated by the isolation wall 70 is a part of the upper region 41, and the in-furnace working device 15 is introduced into the isolation region 73. Accordingly, the cable 15 </ b> A of the in-furnace working device 15 is always positioned in the isolation region 73 of the isolation wall 70.

  The in-furnace working device 15 reaches the annulus part 14 through the isolation region 73 and performs the in-furnace work in the annulus part 14. The cable 15A of the in-furnace working device 15 passes through the isolation region 73 of the isolation wall 70 as described above, and reaches the operation floor 48 along the guide rod 51 and the guide rail 81 (described later). It is connected to the installed control device 74. The in-furnace work of the in-furnace work device 15 is remotely operated by the control device 74. In addition, it is common in each embodiment that the cable 15A of the in-furnace working device 15 is connected to the control device 74 installed on the operation floor 48.

  When the in-core work device 15 performs the in-core work in the annulus portion 14, for example, during periodic inspection, a fuel exchanger (not shown) is installed above the core portion 16 and the core upper region 42, and the core is used by using this fuel exchanger. The replacement work of the fuel 20 of the part 16 may be performed. In this case, the main body 15B and the cable 15A of the in-furnace working device 15 may move to an unexpected region due to the flow of the reactor water, and may interfere with the fuel exchanger and the fuel, but the in-furnace working device 15 is isolated. The interference is avoided by introducing the cable 15A into the isolation region 73 by the wall 70 and always positioning the cable 15A in the isolation wall 73.

  The isolation wall 70 is installed at a position facing a part of the feed water sparger 21 in the reactor pressure vessel 11. As a result, the cooling water ejected from a part of the water supply sparger 21 collides with the isolation wall 70 and changes its direction, flows down in the isolation region 73 and is guided into the annulus portion 14, thereby cooling the annulus portion 14. To do. A fuel 20 is mounted on a core portion 16 adjacent to the annulus portion 14 via a core shroud 13, and an upward flow of reactor water in a high temperature state is caused by the decay heat of the fuel 20 even during regular inspection. The reactor water is assumed to flow over the upper end portion of the isolation wall 40 and flow into the annulus portion 14. However, a part of the cooling water ejected by the water supply sparger 21 is guided into the annulus part 14 through the isolation wall 40 and cools the inside of the annulus part 14, so that the inside of the annulus part 14 is in the in-furnace working device 15. It is kept in an environment close to a temperature environment suitable for.

  The isolation wall constituting members 71 and 71A constituting the isolation wall 70 are common except that the lowermost isolation wall constituting member 71A includes a guide roller 75 as shown in FIGS. That is, the separating wall constituting members 71 and 71A are provided on the curved surface-shaped member main body 76, the guide mechanism portion 77 installed at the upper and lower portions of the central portion of the member main body 76, and the upper portion of the central portion of the member main body 76. One or a plurality of hanging wires 78 attached and a plurality of wheels 79 installed at both ends of the member main body 76 are configured.

  The guide mechanism portion 77 is formed in a U-shaped cross section, and rollers 80 are rotatably attached to a plurality of locations on both inner side surfaces and back side surfaces. A guide rod 51 and a later-described guide rail 81 are fitted in the guide mechanism portion 77, and a roller is used when the isolation wall constituting members 71 and 71A using the suspension wire 78 are suspended and lifted in the reactor pressure vessel 11. 80 rolls in contact with the guide rod 51 or the guide rail 81, and the suspension of the separating wall constituting members 71 and 71A is smoothly guided. The wheel 79 rolls in contact with the inner surface of the reactor pressure vessel 11 when the isolation wall constituting members 71, 71 </ b> A are suspended or lifted in the reactor pressure vessel 11. , 71A is adjusted.

  Further, the guide roller 75 in the lowermost separating wall constituting member 71 </ b> A is rotatably installed on both opposite sides of the lower end of the member main body 76. As a result, the cable 15A of the in-furnace working device 15 positioned in the isolation region 73 of the isolation wall 70 contacts the guide roller 75, and the movement of the cable 15A is smoothly guided.

  As shown in FIG. 14, in the reactor pressure vessel 11 and the reactor well 63, a guide rod 51 extending in the vertical direction and connected to each other and a guide rail 81 as a guide member are installed, and a pulley is also installed. A mechanism 82 is installed at the upper end of the reactor pressure vessel 11.

  As shown in FIGS. 15 and 16, the guide rail 81 has a fitting hole 83 formed in the lower end portion, and the fitting hole 83 is fitted into the upper end portion of the guide rod 51. As shown in FIG. 11, the upper end side of the guide rail 81 is fixed to the handrail 84 of the operation floor 48 directly or via a support (not shown). Further, the guide rail 81 is formed in a square cross section as shown in FIG. The guide mechanism 77 of the isolation wall constituting members 71 and 71A is fitted to the guide rod 51 and the guide rail 81, and the suspension and lifting of the isolation wall constituting members 71 and 71A are smoothly guided.

  Further, the pulley mechanism 82 is installed between stud bolts 85 installed at the upper end of the reactor pressure vessel 11 as shown in FIGS. 15 and 16. The pulley mechanism 82 does not necessarily have to be spanned between adjacent stud bolts 85, and may be installed between two stud bolts 85 that are installed every other one or more. The pulley mechanism 82 includes a seating portion 86 attached to the tip of the stud bolt 85, and a roller 88 that is rotatably supported by the seating portion 86 via a rotation shaft 87. The pulley mechanism 82 is a suspension wire 78 of the isolation wall constituting members 71 and 71A that are suspended or lifted along the guide rail 81 and the guide rod 51 in the reactor pressure vessel 11 or a furnace introduced into the isolation wall 70. The roller 88 comes into contact with the cable 15A of the internal working device 15 to smoothly guide the suspension wire 78 and the cable 15A and avoid interference with the upper end portion of the reactor pressure vessel 11.

  Next, the process from the installation of the isolation wall 70 in the reactor pressure vessel 11 to the operation in the reactor by the in-reactor 15 and the subsequent removal of the isolation wall 70 outside the reactor pressure vessel 11 will be described. To do.

  First, after opening the upper portion of the reactor pressure vessel 11, the pulley mechanism 82 is placed on the stud bolt 85 in a situation where the reactor well 63 of the reactor building is in an air environment or an underwater environment (in this embodiment, an air environment). And a guide rail 81 is fitted and fixed to the upper end of the guide bar 51. The upper part of the guide rail 81 is fixed to the handrail 84 on the operation floor 48 directly or via a support (not shown). At this time, in order to change the installation state of the pulley mechanism 82 in an underwater environment after the reactor well 63 is full, an operation rope or wire (both not shown) is provided as a part of the pulley mechanism 82. You may be tied up.

  Thereafter, the reactor pressure vessel 11 and the reactor well 63 are filled with water in preparation for removing the steam separator and the shroud head (both not shown). When the reactor well 63 becomes full, the steam separator and the shroud head are removed. After filling the reactor well 63 with water, a main steam line plug (not shown) is attached to the steam outlet nozzle. In this embodiment, the ring garter (not shown) of the plug is removed.

  In the reactor pressure vessel 11, when there is nothing on the core shroud 13, first, the guide mechanism portion 77 of the lowermost isolation wall constituting member 71 </ b> A is fitted on the guide rail 81 on the operation floor 48. Then, the suspension wire 78 is sent to cause the isolation wall constituting member 71A to enter the reactor well 63. At this time, since the guide rail 81 has a quadrangular cross section, the roller 80 of the guide mechanism portion 77 in the separating wall constituting member 71A rolls in contact with the upper surface and the side surface of the guide rail 81, thereby separating the separating wall constituting member. The posture of 71A is kept substantially constant.

  Then, the lowermost separating wall constituting member 71 </ b> A moves to the guide rod 51 via the bent portion of the guide rail 81. The guide rod 51 has a circular cross section, but the wheel 79 of the isolation wall constituting member 71A comes into contact with the inner surface of the reactor pressure vessel 11, and the posture thereof is maintained appropriately. At this time, the separating wall constituting member 71 </ b> A can smoothly get over the wheel 79 even when passing vertically through the feed water sparger 21 or the core spray line 49 by the wheels 79.

  The suspension wire 78 of the lowermost separation wall constituting member 71A is guided by the roller 88 of the pulley mechanism 82 and guided into the reactor pressure vessel 11, so that an operator (not shown) directly from the operation floor 48 can directly Or it becomes possible to operate via a hoist (not shown).

  After the lowermost isolation wall constituting member 71A is suspended from the reactor core shroud 13 and installed, the isolation wall constituting member 71 is successively suspended and installed in the reactor pressure vessel 11 in the same procedure as described above. The isolation wall 70 is constructed by stacking the individual pieces, and an isolation region 73 for introducing the in-furnace working device 15 is formed.

  At the stage where the isolation wall 70 is constructed on the core shroud 13, the in-reactor work device 15 is carried into the reactor pressure vessel 11. At this time, the in-reactor work device 15 may be suspended from a work platform (not shown) installed on the upper part of the reactor well 63 and may enter or enter the reactor pressure vessel 11. Using a propulsion device (not shown), the pulley mechanism 82 may be passed through the inside of the reactor pressure vessel 11 by swimming.

  The in-furnace working device 15 is suspended near the guide rod 51, passes through the isolation region 73 of the isolation wall 70, and reaches the annulus portion 14. In the annulus section 14, the in-furnace working device 15 approaches a predetermined target part and performs various in-furnace operations by remote control from the control device 74. At this time, a self-propelled function (not shown) may be provided in the in-furnace working device 321. In particular, even in the case where the reactor working vessel 15 is accompanied by the movement of the reactor pressure vessel 11 in the circumferential direction, the guide roller 75 is installed on the lowermost separating wall constituting member 71A constituting the separating wall 70 and the cable 15A is connected. Since it is guided, the cable 15A can move within a predetermined range without being caught by the lower end portion of the lowermost separating wall constituting member 71A.

  When the in-furnace work by the in-furnace work apparatus 15 is completed, the in-furnace work apparatus 15 is moved directly below the isolation region 73 in the isolation wall, the cable 15A and the like are pulled up, and the in-furnace work apparatus 15 is moved to the operation floor 48. Remove to the top.

  Next, the suspension wire 78 of the isolation wall constituting member 71 installed at the top of the isolation wall 70 is pulled up, and the isolation wall constituting member 71 is moved up to the operation floor 48 via the guide rod 51 and the guide rail 81. Take out and remove out of the reactor pressure vessel 11. Thereafter, the other isolation wall constituting member 71 and the lowermost isolation wall constituting member 71A are removed out of the reactor pressure vessel 11 in the same procedure.

  Next, the main steam line plug attached to the steam outlet nozzle is removed, and the shroud head and the steam separator are installed in the reactor pressure vessel 11. Then, after the reactor water level is lowered to the upper end level of the reactor pressure vessel 11, the pulley mechanism 82 and the guide rail 81 are removed under an atmospheric environment.

  Since it is configured as described above, the following effects can be obtained according to the present embodiment.

  That is, the upper region 41 of the annulus part 14 and the core upper region 42 are separated by the isolation wall 70, and the isolation region 73 formed by the isolation wall 70 (that is, a part of the upper region 41) An in-furnace working device 15 is introduced which works in Therefore, even when the replacement operation of the fuel 20 by the fuel exchanger in the core portion 16 is performed in parallel with the in-furnace operation by the in-furnace operation device 15, the main body 15B of the in-furnace operation device 15 and its cable Since the movement of 15A is regulated by the isolation wall 70, it is possible to prevent the main body 15B and the cable 15A of the in-furnace working apparatus 15 from interfering with the fuel exchanger and the fuel. For this reason, the possibility of interruption of both operations due to the occurrence of interference can be reduced, and the load of monitoring activities for avoiding interference can be reduced.

  Further, the isolation wall 70 is installed in the reactor pressure vessel 11 at a position facing a part of the water supply sparger 21, whereby the cooling water ejected from a part of the water supply sparger 21 flows down in the isolation region 73 and becomes an annulus. Since it is guided into the portion 14, the inside of the annulus portion 14 can be cooled. As a result, since the inside of the annulus portion 14 can be maintained in an environment close to the temperature environment suitable for the in-furnace working device 15, failure due to heat of the in-furnace working device 15 can be reduced, and its soundness, reliability and durability can be reduced. It can be secured.

  In addition, also in the present embodiment, the in-furnace working device 15 is introduced into the isolation region 73 of the separating wall 70, so that the separating wall 70 guides the in-furnace working device 15. It is possible to quickly reach the target work position.

  As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to this. For example, although the above embodiment has described the case of a boiling water reactor, the present invention can also be applied to a pressurized water reactor. In this case, the reactor pressure vessel of each embodiment corresponds to a reactor vessel.

1 is a system diagram showing a first embodiment of an in-furnace work system according to the present invention. The flowchart which shows the procedure which the in-furnace thermal fluid state determination apparatus of FIG. 1 performs. The graph which shows the operable range of the in-furnace working apparatus of FIG. It is 2nd Embodiment of the reactor internal work system which concerns on this invention, (A) is a semi-longitudinal sectional view which shows the internal structure of a reactor pressure vessel, (B) is the IV-IV line of FIG. 4 (A). FIG. It is 3rd Embodiment of the in-core work system which concerns on this invention, (A) is a half longitudinal cross-sectional view which shows the internal structure of a reactor pressure vessel, (B) is the VV line | wire of FIG. 5 (A). FIG. It is 4th Embodiment of the in-core working system which concerns on this invention, (A) is a half longitudinal cross-sectional view which shows the internal structure of a reactor pressure vessel, (B) is VI-VI line of FIG. 6 (A). FIG. 8 is a fifth embodiment of an in-core work system according to the present invention, in which (A) is a semi-longitudinal sectional view showing an internal structure of a reactor pressure vessel, and (B) is a line VII-VII in FIG. 7 (A). FIG. The longitudinal cross-sectional view which shows the internal structure of the reactor pressure vessel in 6th Embodiment of the in-core work system which concerns on this invention. (A) is a view on arrow A in FIG. 8, (B) is a view on arrow B in FIG. 9 (A). (A) is a top view which shows the suspended state of the isolation wall of FIG. 8, (B) is sectional drawing which follows the XX line of FIG. 10 (A). The longitudinal cross-sectional view which shows the internal structure of the reactor pressure vessel in 7th Embodiment of the in-core work system which concerns on this invention. The perspective view which shows the isolation wall structural member of FIG. FIG. 12 is a perspective view showing a lowermost isolation wall constituting member in FIG. 11. The longitudinal cross-sectional view which shows the inside of the reactor pressure vessel before the isolation wall installation in FIG. The perspective view which shows the pulley mechanism etc. of FIG.11 and FIG.14. The longitudinal cross-sectional view which shows the pulley mechanism etc. of FIG.11 and FIG.14.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Reactor pressure vessel 12 Reactor cooling system 13 Core shroud 14 Annulus part 15 In-furnace working device 15A Cable 21 Water supply sparger 24 Reactor heat flow state judgment device 30 Water supply sparger enclosure (introduction structure)
31 Cooling water transfer pipe (introduction structure)
32 Enclosure (Introduction structure)
33 Cooling water inlet (introduction structure)
40 Isolation wall 41 Upper region 42 Core upper region 43 Isolation region 50 Engagement piece (engagement part)
51 Guide rod 53 Hanging ear (hanging part)
55 Lifting jig 56 Overhead crane coupling part 57 Lifting cylinder 70 Isolation wall 71 Isolation wall constituting member 71A Bottom isolation wall constituting member 73 Isolation region 75 Guide roller 77 Guide mechanism 78 Suspension wire 81 Guide rail 82 Pulley mechanism

Claims (15)

In the in-core work system that works inside the reactor pressure vessel using the in-core work device,
Operation control of the reactor cooling system for supplying cooling water into the reactor pressure vessel according to the temperature and flow state of the reactor water in the region including the work target part,
Installation of an introduction structure for introducing cooling water from the reactor cooling system into an area including the work target part;
An isolation wall for isolating an upper region of the region including the work target part, guiding the in-core work device into the isolation region, and guiding cooling water from the reactor cooling system to the region including the work target part. Carry out at least one of the installation and
An in-furnace work system characterized in that a work target part is worked by the in-furnace work device. Operation control of the reactor cooling system is performed based on the temperature and flow velocity of the reactor water in the region including the work target, and the reactor thermal fluid state determination device determines the thermal fluid state in the reactor pressure vessel, and the reactor Implemented by selecting either the operation mode in which the operation of the cooling system is stopped and the in-reactor operation is performed by the in-reactor or the cooling operation mode in which the reactor cooling system is operated without performing the operation in the reactor The in-furnace work system according to claim 1, wherein The in-furnace thermal fluid state determination device sets an upper limit temperature and an upper limit flow velocity for the in-furnace work device, the reactor water temperature in the region including the work target part is equal to or lower than the upper limit temperature, and the reactor water in the region The in-furnace work system according to claim 2, wherein the work mode is selected when the flow rate is equal to or lower than the upper limit flow rate, and the cooling operation mode is selected in other cases. The in-furnace thermal flow state determination device obtains the reactor water temperature and the reactor water flow velocity in the region including the work target portion by data analysis, and selects either the operation mode or the cooling operation mode based on the temperature and the flow velocity. The in-furnace working system according to claim 2 or 3, characterized in that. The introduction structure for introducing the cooling water from the reactor cooling system is to introduce the cooling water into the annulus portion defined by the reactor pressure vessel and the core shroud as the region including the work target portion. 2. The in-furnace work system according to claim 1, wherein The introduction structure for introducing the cooling water from the reactor cooling system is arranged along the feed water sparger installed above the core shroud in the reactor pressure vessel and spaced apart from the core shroud side of the feed water sparger. The in-furnace work system according to claim 5, which is a water supply sparger enclosure. The introduction structure for introducing cooling water from the reactor cooling system includes a water supply sparger enclosure plate and a cooling water transfer pipe extending from a plurality of locations of the water supply sparger enclosure plate toward the annulus portion. The in-furnace work system according to claim 6, wherein The introduction structure for introducing cooling water from the reactor cooling system is provided at a position facing a feed water sparger that supplies cooling water from the reactor cooling system into the reactor pressure vessel, and is provided at the upper end of the core shroud. The in-furnace work system according to claim 5, wherein the work system is an installed shroud. 6. The introduction structure for introducing cooling water from the reactor cooling system is a cooling water inlet provided in the reactor pressure vessel in communication with the annulus portion of the reactor pressure vessel. The in-furnace work system described. The isolation wall is installed in a core shroud installed in the reactor pressure vessel, and defines an upper area of the annulus portion as an area including a work target site, which is defined in the reactor pressure vessel and the core shroud. 2. The in-core work system according to claim 1, wherein the in-core work system is isolated from an upper region of the core. The isolation wall includes an engaging portion that engages with a guide rod installed in a vertical direction in the reactor pressure vessel, and is guided by the engagement between the engaging portion and the guide rod. The in-furnace work system according to claim 10, wherein A suspension part is provided on the upper part of the isolation wall, and a suspension jig coupled to an overhead crane is connected to the suspension part so that the isolation wall is suspended in the reactor pressure vessel. The in-furnace work system according to claim 10, wherein the in-furnace work system is lifted and removed. The isolation wall isolates the upper region of the annulus portion, which is defined by the reactor pressure vessel and the core shroud and includes the work site, from the upper region of the reactor core, and a plurality of isolation wall components The in-furnace work system according to claim 1, wherein the in-furnace work system is configured to be stacked in a direction. Each isolation wall component includes a guide mechanism and a suspension wire, and includes a guide rod installed in a vertical direction in the reactor pressure vessel and a guide member extending from the upper end of the guide rod to the operation floor. The guide mechanism portion is fitted to guide the isolation wall constituent member, and the suspension wire of the isolation wall constituent member is guided to a pulley mechanism provided at the upper part of the reactor pressure vessel. The in-reactor work system according to claim 13, wherein the isolation wall constituting member is suspended and installed in the reactor pressure vessel, and is lifted and removed. 15. The guide roller for guiding the cable of the in-furnace working device is installed at the lower end of the isolation wall constituent member located at the lowest stage among the isolation wall constituent members. In-furnace work system.

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